Parents have been warned not to fall asleep with their baby on a bed or a sofa until the child is at least one year old.

New draft recommendations from health watchdog National Institute for Health and Care Excellence (Nice) say parents can easily suffocate their babies while they are asleep.

And the risk is higher if they have drunk alcohol, taken drugs or smoked.

Babies are also more likely to die suddenly in their sleep if they were born small or premature.

Professor Mark Baker, Nice's clinical practice director, said: "Falling asleep with a baby, whether that's in a bed or on a sofa or chair, is risky.

"We recognise that some parents may choose to share a bed with their baby because it could make breastfeeding easier, or for cultural reasons.

"Or they may be forced to co-sleep because they may not have the space or money for a cot.

"This is why it's so important for parents to understand what the risks are."

Just under 250 babies a year die from sudden infant death syndrome (SIDS) in England and Wales.

Doctors still do not understand what causes babies to die. But Nice says the risk factors are becoming clearer.

Existing advice warns parents not to "co-sleep" with their babies until they are six to eight weeks old.

Nice says new research shows the risk period extends up to one year.

SIDS charity The Lullaby Trust said it regularly has contact with families that have lost a baby older than eight weeks.

Francine Bates, chief executive, said: "If every parent followed these guidelines we believe we could go a long way in achieving our ambition of halving the rate of SIDS in this country by 2020."

But Belinda Phipps, chief executive of the National Childbirth Trust, warned exhausted parents are likely to ignore the advice.

"We know that around half of UK mothers bed-share with their baby at some point in their first few months," she said.

"Nice guidance needs to reflect this reality. We are concerned that these guidelines will lead to parents hiding the fact that they are bed-sharing, or doing so through desperation or exhaustion without safety strategies in place."